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动态负荷下髋臼假体长期稳定性的生物力学测试

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中华外科杂志 2004年第20期42卷 1228-1231页

作者：吴杰 K-h.widmer b.Zurfluh b.Goepfert e.w.morscher 首都医科大学附属北京友谊医院骨科 100050 Department of Orthopaedics Beijing Friendship Hospital

目的　在动态负荷下测量骨水泥固定及生物性固定髋臼假体与骨交界面的相对运动 ,评价骨水泥及非骨水泥髋臼假体的长期稳定性。方法　在体外利用已植入全髋关节假体的标本 ,模拟动态生理负荷状态下髋关节活动 ,将微力学三维传感器固定于... 详细信息

目的　在动态负荷下测量骨水泥固定及生物性固定髋臼假体与骨交界面的相对运动 ,评价骨水泥及非骨水泥髋臼假体的长期稳定性。方法　在体外利用已植入全髋关节假体的标本 ,模拟动态生理负荷状态下髋关节活动 ,将微力学三维传感器固定于假体与骨交界面不同点 ,测量骨水泥固定及生物性固定髋臼假体与骨交界面的相对运动。结果　放射学显示生物型假体周围均未发现骨溶解。使用骨水泥固定的髋臼假体 ,骨与假体交接面的相对运动可达 90 μm ,而使用生物固定的髋臼假体 ,骨与假体交接面的相对运动为 6 0 μm。结论　通过实验结果的综合分析 ,生物性固定Press fit髋臼假体与骨水泥固定聚乙烯髋臼假体在体内存活时间存在较大差异 ,无法对两者的长期稳定性进行统计学比较。但通过实验可以看到生物性固定髋臼假体的相对运动较小 ,有利于骨的生长。

关键词：髋臼假体骨水泥固定生物力学测试生物性长期稳定性骨溶解体长标本发现

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X射线光电光谱表征金属氧化物的酸碱性

地球化学 2010年第3期39卷 280-295页

作者： m. Ding b.h.w.S. deJong earth and environmental Science Division Los Alamos National Laboratory Los Alamos NM 87545 USA Department of earth Sciences Utrecht University Utrecht the Netherlands

本文探讨了氧配位的八面体及四面体的金属配合物中氧原子的价态变化及其酸碱性差异之间的关系。首先利用X射线光电光谱(XPS)分别推导出了氧原子在碱及碱土铝酸盐、铬酸盐、高铁酸盐、钼酸盐及钨酸盐中的价态,随后对氧原子的价态及氧化... 详细信息

本文探讨了氧配位的八面体及四面体的金属配合物中氧原子的价态变化及其酸碱性差异之间的关系。首先利用X射线光电光谱(XPS)分别推导出了氧原子在碱及碱土铝酸盐、铬酸盐、高铁酸盐、钼酸盐及钨酸盐中的价态,随后对氧原子的价态及氧化物的酸碱性质进行了比较。研究结果表明,氧原子的价态在这两种配位构型的化合物中没有显著的差别,其酸碱性的不同在于四面体配位的金属化合物中O2p态在非成键和成键的电子密度中高价带的分裂。

关键词： X射线光电光谱氧化物酸碱性金属配合物氧原子价态

Cardiovascular physiology in the older adults

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Journal of Geriatric Cardiology 2015年第3期12卷 196-201页

作者： Xuming Dai scott L hummel Jorge b Salazar George e Taffet Susan Zieman Janice b Schwartz Division of Cardiology University of North Carolina at Chapel Hill Chapel Hill NC USA Division of Cardiovascular medicine Department of Medicine University of Michigan Ann Arbor Ml Ann Arbor Veterans Affairs Health System Ann Arbor M1 USA Division of Cardiology Mayo Clinic Rochester MN USA Division of Geriatrics Geriatrics and Cardiovascular Sciences Houston Methodist Hospital Baylor College of'Medicine Houston TX USA Division of Geriatrics and Clinical Gerontology National Institute of Aging Bethesda ME) USA Divisions of Geriatrics and Clinical Pharmacology Department of Medicine University of California San Francisco CA USA

1 Introduction In an aging society with persistent high prevalence of cardiovascular disease （CVD） in the elderly population, the health care system is facing an increasing challenge to effectively care for these patients. however, due to the under-representation of CVD patients over 75 years of age in clinical trials, assessing safety and efficacy of diagnostic and therapeutic approaches, the evidence for managing elderly CVD patients is especially limited. Physiological changes of aging intertwined with pathophysiology of CVD, and comorbid conditions often complicate clinical management.

关键词： Aging Cardiovascular disease Left ventricular

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与一类超过程相关的Dirichlet问题

科学通报 1997年第17期42卷 1899-1900页

作者：刘震吴荣南开大学数学系天津300071

设ξ=（∈ι,Πx）是Rd中的右过程,令（?）（x,z）=a（x）z+b（x）z2+ integral from n =1 to ∞(e-uz-1+uz)nx（du）, x∈Rd,z∈R+,（1）考虑下面Dirichlet问题 Av（x）-（?）（x,u（x））=0,x ∈　 D,（2）（?） u（x）=f（a）,a∈... 详细信息

设ξ=（∈ι,Πx）是Rd中的右过程,令（?）（x,z）=a（x）z+b（x）z2+ integral from n =1 to ∞(e-uz-1+uz)nx（du）, x∈Rd,z∈R+,（1）考虑下面Dirichlet问题 Av（x）-（?）（x,u（x））=0,x ∈　 D,（2）（?） u（x）=f（a）,a∈（?）Dr,（3）这里D是Rd中有界区域,（?）Dr表示（?）D中正规点全体,且A是ξ关于D的特征算子. 我们用m表示（?）（Rd）上的有限测度全体,用（?）表示m上由fb（μ）=μ（b）,b∈（?）产生的σ-代数.本文中τ都表示开集D的首出时.根据Dynkin存在取值于（m,（?））的具有参数（ξ,（?））的超过程 X={Xt,Xτ,Pμ,μ∈ m}.Dynkin在文献[1]中证明了如果ξ是光滑一致椭圆算子,关于x局部Lipshitz连续,公式 v（x）=- log Pδexp（-（f, Xτ））（4）是方程（2）Dirichlet问题的唯一解.本文将上面结果推广到一些一般型条件（底过程不一定连续）.

关键词：超过程狄利克雷问题右过程扩散过程

effects of heat input in friction stir welding on microstructure and mechanical properties of AA3003-h18 plates

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Transactions of Nonferrous metals Society of China 2015年第7期25卷 2147-2155页

作者： b.AbNAR m.KAZemINeZhAD A.h.KOKAbI Department of materials Science and engineering Sharif University of Technology

The non-heat-treatable AA3003-h18 plates were joined by friction stir welding（FSw） to achieve a proper joint by optimizing the welding *** this purpose,the effects of heat input on microstructure and mechanical properties of the welded samples were investigated by changing the ratios of rotational speed（800-1200 r/min） to travel speed（40-100 mm/min）（w/v）.It was revealed that the grain growth rate was strongly increased with the increase of the heat input by rotational speed at constant travel speed,while the grain growth rate was slightly increased with the increase of the heat input by travel speed at constant rotational ***,hardness reduction was observed in the stir zone at higher rotational speed compared with that at lower *** interesting observation was that various welding parameters do not have noticeable effect on the tensile strength of the FSw ***,it has been observed that the fracture location of tensile test specimens was placed in the heat-affected zone（hAZ）on the advancing side at lower travel speed,while at higher travel speed,it was placed at the hAZ/thermomechanical affected zone（TmAZ） interface on the retreating side.

关键词： AA3003-h18 alloy friction stir welding heat input microstructure mechanical properties

考虑地下水入侵导致土壤强度变化的沿海建筑地基韧性模型

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岩土力学 2023年第1期44卷 67-74页

作者：王草 AYYUb b.m KUmARI w.G.P 伍伦贡大学土木、采矿与环境学院澳大利亚伍伦贡马里兰大学土木与环境工程学院美国马里兰

海平面上升导致的地下水入侵沿海地区的建筑地基造成显著风险。提出了一个考虑地下水侵入导致土壤强度退化的沿海建筑地基韧性模型。该模型由地基的性能函数在服役期内的积分得到。考虑条形基础的韧性,其极限承载力由Terzaghi公式描述... 详细信息

海平面上升导致的地下水入侵沿海地区的建筑地基造成显著风险。提出了一个考虑地下水侵入导致土壤强度退化的沿海建筑地基韧性模型。该模型由地基的性能函数在服役期内的积分得到。考虑条形基础的韧性,其极限承载力由Terzaghi公式描述。韧性模型考虑气候变化背景下地下水位的上升对土壤强度的影响。通过一个算例,展示了所提出的韧性模型的适用性。结果表明,如果不考虑气候变化影响下地下水位的上升,则会得到不保守的结构韧性评估结果。结构全寿命周期内的韧性也取决于所采用的维护措施(即,修复受损的结构性能)。未来的研究中,还应考虑其他因素(如锈蚀)对沿海建筑地基性能退化的联合影响。

关键词：韧性模型沿海建筑地基土壤强度变化地下水入侵气候变化

b lymphocytes regulate airway granulocytic inflammation and cytokine production in a murine model of fungal allergic asthma

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Cellular & molecular Immunology 2015年第2期12卷 202-212页

作者： Sumit Ghosh scott A hoselton scott V Asbach breanne N Steffan Steve b wanjara Glenn P Dorsam Jane m Schuh Department of Veterinary and microbiological Sciences North Dakota State University Fargo ND USA

Sensitization to fungi often leads to a severe form of asthma that is particularly difficult to manage clinically, resulting in increased morbidity and hospitalizations in these patients. Although b lymphocytes might exacerbate asthma symptoms through the production of Ige, these cells might also be important in the protective response against inhaled fungi. Through cytokine release and T-cell interactions, these lymphocytes might also influence the development and maintenance of airway wall fibrosis. Jh-/- mice lack the Jhgene for the heavy chain component of antibodies, which is critical for b-cell function and survival. These animals have facilitated the elucidation of the role of b iymphocytes in a number of immune responses; however, Jh-/- mice have not been used to study fungal allergy. In this study, we examined the role of b lymphocytes using an Aspergillus fumigatus murine fungal aeroallergen model that mimics human airway disease that is triggered by environmental fungal exposure. we compared disease progression in sensitized wild-type bALb/c and Jh-/- mice that were exposed to repeated fungal exposure and found no differences in airway hyperresponsiveness, overall pulmonary inflammation or collagen deposition around the large airways. however, the levels of the Th2-type cytokines IL-4 and IL-13 were significantly attenuated in the airways of Jh-/- mice relative to the bALb/c controls. by contrast, levels of the inflammatory cytokines IL-17A and IL-6 were significantly elevated in the Jh-/- animals, and there was significantly more robust airway eosinophilia and neutrophilia than in control animals. Taken together, these findings demonstrate that b lymphocytes help to regulate granulocytic responses to fungal exDosure in the pulmonary compartment.

关键词： Aspergillus fumigatus b lymphocytes inflammation

Conceptual design of oil palm fibre reinforced polymer hybrid composite automotive crash box using integrated approach

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Journal of Central South University 2020年第1期27卷 64-75页

作者： N S b YUSOF S m SAPUAN m T h SULTAN m JAwAID Laboratory of biocomposite Technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Faculty of Information Sciences and engineering Management and Science UniversitySeksyen 1340100 Shah AlamSelangorMalaysia Advanced engineering materials and Composites Research Centre Department of Mechanical and Manufacturing EngineeringUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia Department of Aerospace engineering Universiti Putra Malaysia43400 UPM SerdangSelangorMalaysia

A hybrid conceptual design approach was introduced in this study to develop a conceptual design of oil palm polymer composite automotive crash box(ACb). A combination of theory of inventive problem solving(TRIZ), morphological charts and biomimetics was applied where the foremost requirements in terms of the material characteristics, function specifications, force identification, root cause analysis, geometry profile and design selection criteria were considered. The strategy was to use creations of nature to inspire five innovative conceptual designs of the ACb structure and the AhP method was applied to perform the pairwise analysis of selecting the best ACb conceptual design. A new conceptual design for a composite ACb was conceived bearing in mind the properties of natural fibre, unlike those of conventional materials such as steel alloys and aluminium alloys. The design with the highest ranking(26.6 %) was chosen as the final conceptual design, which was the one with a honeycomb structure for the outermost profile, reinforced with a spider web structure inside the part, supported by fibre foam structure extracted from the woodpecker sponge tissue at the centre to maximize the energy absorption capability. The new design could solve the problem of bending collapse which is a major cause of failure to absorb maximum impact energy for ACb during collision. however, the final conceptual design will still need several modifications for production and assembly purposes, which will be completed in a further study.

关键词： conceptual design automotive crash box hybrid method concept selection method

增材制造Ti6Al4V合金的闪速等离子体电解氧化与在生理介质中的电化学行为

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Transactions of Nonferrous metals Society of China 2024年第4期34卷 1150-1166页

作者： h.mORA-SANCheZ C.RAmOS m.mOheDANO b.TORReS R.ARRAbAL e.mATYKINA Departamento de Ingeniería Química y de materiales Facultad de Ciencias QuímicasUniversidad Complutense de Madrid28040 MadridSpain CIDeTeC Basque Research and Technology Alliance(BRTA)Po.Miramón 19620014 Donostia-San SebastiánSpain Departamento matemática Aplicada Ciencia e Ingeniería de Materiales y Tecnología ElectrónicaUniversidad Rey Juan CarlosC/Tulipán s/nMóstoles 28933MadridSpain

研究激光粉末床熔融增材制造(Am)(又称直接金属激光烧结)技术制备的Ti6Al4V合金等离子体电解氧化(PeO)处理及其电化学行为。通过短时间(<120 s)PeO处理(也称闪速PeO),在Am合金和传统合金表面制备了3~10μm厚、含Ca和P的涂层。然后在改... 详细信息

研究激光粉末床熔融增材制造(Am)(又称直接金属激光烧结)技术制备的Ti6Al4V合金等离子体电解氧化(PeO)处理及其电化学行为。通过短时间(eO处理(也称闪速PeO),在Am合金和传统合金表面制备了3~10μm厚、含Ca和P的涂层。然后在改良的α-mem溶液中,通过动电位极化曲线和电化学阻抗谱(eIS)评估了合金的电化学行为。与传统合金相比,Am合金中形成了细小的层片状α显微组织和层间小尺寸的β相颗粒,这促使了火花的产生,从而促进了PeO涂层的生长。闪速PeO涂层提高了传统合金和Am合金的耐腐蚀性,最薄的涂层(m)提供了高达3倍的保护。Am Ti6Al4V由于其高的晶界密度,易受局部缝隙腐蚀的影响。而即使短至35 s的闪速PeO处理也足以成功避免这种情况。

关键词：增材制造激光粉末床熔融等离子体电解氧化闪速PeO 钛缝隙腐蚀 α-mem

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